Muscle Physiology Skeletal muscle function. Muscle Strength A motor unit is one motor neuron and all...
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- Slide 1
- Muscle Physiology Skeletal muscle function
- Slide 2
- Muscle Strength A motor unit is one motor neuron and all of the
muscle fibers it controls The force with which a whole muscle
contracts depends on how many motor units the nervous system
stimulates.
- Slide 3
- All or None.. A muscle will either completely contract, or not
at all. This means the stimulus only needs to pass the
threshold.
- Slide 4
- What is the threshold? The minimum amount of stimulation that
will cause a muscle fiber to completely contract. The amount of
work that a muscle is being asked to perform is directly
proportional to the threshold of the stimulus.
- Slide 5
- Types of muscle contractions Isometric: Muscle increases in
tension but does not shorten Isotonic: The muscle shortens and the
amount of tension is constant. Most muscle movement is a
combination of both types of contractions.
- Slide 6
- Slide 7
- Muscle Fatigue Fatigue is the decrease in ability to do work
Psychological fatigue is when a person thinks he/she cannot do any
more muscular work Muscle fatigue means the muscles have trouble,
or are unable to respond to stimuli
- Slide 8
- Energy for muscle contraction Creatine phosphate can be used as
an energy source for ATP production. Most ATP is produced during
aerobic respiration
- Slide 9
- Oxygen and exercise Heavy exercise creates EPOC excess post-
exercise oxygen consumption The time spent in EPOC depends on each
persons level of fitness Fat metabolism is also a factor because
more oxygen is required to generate energy from fats
- Slide 10
- Hypertrophy and Atrophy Hypertrophy is an increase in a muscles
size Most hypertrophy is due to exercise Atrophy is a decrease in
muscle size This is usually due to disuse.